1. Field of the Invention
Exemplary embodiments relate to a communication method of a base station and a terminal based on interference alignment in a multi-cell multi-user multiple-input multiple-output (MIMO) interference channel.
Also, exemplary embodiments relate to a method and apparatus for communication using interference alignment and block successive interference pre-cancellation in a multi-user MIMO interference channel.
2. Description of the Related Art
With an increase in data communication services, more interference signals are being transmitted from a plurality of terminals and access points (APs). Accordingly, the data communication services are faced with limitations in increasing communication capacity and communication quality deterioration.
Conventionally, an increased number of APs is employed to deal with poor communication areas or increase communication capacity. However, as a number of APs reaches a threshold or greater and a size of a cell is reduced, an influence of interference signals transmitted from adjacent APs increases remarkably. Recently, extensive studies are being conducted on wireless communication in a small cell such as a micro-cell or a femto-cell.
However, a cell planning technique to reuse an existing frequency or a multiple-input multiple-output (MIMO) scheme using multiple antennas, both of which are directed to decreasing interference, has a limitation in terms of controlling the interference.
In addition, although an interference alignment technique using multiple antennas to increase cell capacity has been suggested, the interference alignment technique involves a great amount of channel information to calculate an interference alignment weight and a substantial amount of calculation.
Conversely, with an increase in data communication service users, more interference signals between multiple transmitters and multiple receivers are being generated. Thus, the communication capacity limit is reached and the communication quality deteriorates because of these interference signals.
To resolve these issues, an increased number of APs is conventionally employed to deal with poor communication areas or increase the communication capacity. However, as a number of APs reaches a threshold or greater, and a size of a cell is reduced, an influence of interference signals transmitted from adjacent APs increases remarkably.
Recently, an interference alignment technique using multiple antennas has been suggested to increase the cell capacity. However, the interference alignment technique remains unknown as to solutions of precoding/decoding for perfect interference alignment with any number of general antennas and terminals.
Accordingly, the present disclosure proposes to introduce pre-cancellation to an interference alignment technique to obtain a higher multiplexing gain or more degrees of freedom (DOF) than conventional interference alignment.